Deleting a comment because it is insulting a person is moderation. Deleting a comment because you don't like it, it doesn't conform to your views or you find it outrageous, silly, inflammatory, false, fake is censorship.
Your comment brings this out because some subset of "outrageous, silly, inflammatory, false, fake" is right on the cusp, and making those calls (to moderate or not to moderate?) puts tremendous pressure on one's own feelings and beliefs. What helps one do it neutrally is self-awareness, but that is the scarcest thing there is. It takes a decade of hard work to distill a bit more. (Edit: and I'm not claiming to have much; just that it's needed.)
I'm uncomfortable with the "false" / "fake" end of your spectrum because we don't have a truth meter. Who am I to decide what's true or false or "mis" or "dis" for anybody else? I'm not taking on that karma.
"Inflammatory" is easier to work with because it's about predictable community effects and one can moderate for community cohesion. Moderating that way ends up excluding truths that the community can't withstand, but such truths probably exist for any community. Groups may even be defined by what they exclude. We can try to stretch those limits but there's only so much elasticity available.
I blanched when I read "Moderation is the normal business activity of ensuring that your customers like using your product" in the OP, but actually that's basically saying moderation is about community cohesion and I can't disagree. But the secret agenda, on HN at least, is to stretch it.
...Is it? I mean, compared to Twitter, sure, but for a private forum I think of it as relatively large.
HN feels mid-size in a good way. Most forums are a lot smaller, and then there are the few famous ones that are much much larger. There aren't that many in HN's order of magnitude. The mid range is a nice place to hang because although the problems are impossible, they're not utterly impossible. You can work with them around the margins.
The most interesting number is the 1300 submissions because that hasn't grown since 2011 - it just fluctuates. Everything else has been growing more or less linearly for a long time, which is how we like it.